Purpose: Uric acid (UA) is thought to exert neuroprotective roles. The purpose of this study was to examine the association of serum UA with suicide attempts (SA) in adolescents and young adults with major depressive disorder (MDD).
Patients and Methods: We retrospectively recruited  533 participants with MDD aged 13 to 25 years, of which 168 had a history of SA in the past three months and 365 did not have a history of SA. Serum UA levels were measured using the uricase-peroxidase coupling method. In addition to overall serum UA level comparison in MDD individuals with and without SA, a stratified analysis by biological sex was carried out.
Results: Compared to MDD individuals without a history of SA, serum UA levels were significantly lower in MDD individuals with SA (P < 0.001). Female MDD, but not male MDD individuals, with SA exhibited lower levels of UA than those without SA (P < 0.01). Importantly, serum UA remained significantly associated with SA in MDD individuals (OR = 0.996, 95% CI: 0.993∼ 0.999, P < 0.01) when controlling for possible confounding variables.
Conclusion: This research identifies a relationship between serum UA levels and SA in adolescents and young adults with MDD. UA may represent a biological risk marker for SA, in particular for female MDD individuals.
Keywords: suicide, MDD, uric acid, antioxidant, oxidative stress, biomarker